Iron deficiency

Question 1

Inorganic iron salts exists in 2 forms

Answer 1

– Ferrous (2+) “reduced” : gained an electron
– Ferric (3+) “oxidized” : lost an electron

Question 2

is an essential element in humans, being the central ion in heme (the non-protein component of hemoglobin, myoglobin, and cytochromes)

Answer 2

iron

Question 3

Iron deficiency causes a failure

Answer 3

in heme synthesis

Question 4

Iron deficiency results in the production of red cells that are

Answer 4

smaller than normal (microcytic) and paler than normal (hypochromic)

Question 5

an essential component of hemoglobin, and is responsible for binding oxygen in a pocket between the globin chain and the porphyrin plate.

Answer 5

Iron in the ferrous form

Question 6

iron deficiency leads to

Answer 6

anemia and tissue hypoxia

Question 7

what is highly toxic to the cells and must be bound to protein at all time

Answer 7

Free iron

Question 8

what is Haber-Weiss reaction

Answer 8

Fe+2 + H2O2 Fe+3 + OH- + OH

Question 9

Free-radicals can attack:

Answer 9

– Cellular membranes - DNA – Proteins

Question 10

Iron excess possibly related to

Answer 10

cancers and cardiac toxicity

Question 11

about (_) of iron is lost from the body per day

Answer 11

1 mg

Question 12

how is iron usually lost

Answer 12

through sloughed mucosal epithelial cells or blood loss

Question 13

The majority of iron required by the body is acquired by

Answer 13

recycling iron from senescent red cells.

Question 14

2 ml of blood contains approximately (_) of iron.

Answer 14

1 mg

Question 15

Daily red cell production requires

Answer 15

20 - 25 mg Fe2+

Question 16

only (_) of iron is absorbed each day from the diet

Answer 16

1 - 1.5 mg

Question 17

Adult human body contains about

Answer 17

3000-4000 mg of iron

Question 18

Most of the iron within the body is found in

Answer 18

hemoglobin within erythrocytes (about 1800 mg of iron)

Question 19

Iron is also stored in macrophages and in hepatocytes, which represents the storage pool of iron

Answer 19

about 1600 mg of iron

Question 20

Storage iron occurs in two forms

Answer 20

– Ferritin (soluble)
– Hemosiderin (insoluble)

Question 21

Excess iron can be complexed to phosphate and
hydroxide to form

Answer 21

hemosiderin

Question 22

Abnormal quantities of hemosiderin can occur

Answer 22

after internal hemorrhage (bruising)

Question 23

Hemosiderin can also accumulate inside cells that normally

Answer 23

metabolize red blood cells, if there is increased red blood cell breakdown

Question 24

accumulations of hemosiderin occur in the liver

Answer 24

in some kinds of anemia or after large numbers of blood transfusions

Question 25

a glycoprotein synthesized in the liver having a central role in the body’s metabolism of iron

Answer 25

Transferrin

Question 26

Each mole of transferrin can transport

Answer 26

2 moles of Fe3+

Question 27

how does the iron dissociate from transferrin

Answer 27

The acidic pH of the lysosome

Question 28

Dietary iron is obtained from

Answer 28

from inorganic (non- heme Fe 3+) or animal sources via (heme Fe 2+)

Question 29

Plasma transfer of iron from enterocytes to the transport protein, (_) , occurs through specific iron channels, called (_) and is facilitated by a protein called (_)

Answer 29

apotransferrin ferroportins hephaestin

Question 30

When apotransferrin binds iron, it is called

Answer 30

transferrin

Question 31

a main iron regulating protein decreases ferroportin and thus decreases iron absorption

Answer 31

Hepcidin

Question 32

Iron absorption mainly takes place in

Answer 32

proximal small intestine

Question 33

half clearance time of transferring bound iron is

Answer 33

60-90 minutes

Question 34

Iron absorbed from the intestine is stored as (_) in (_) epithelium or transported in plasma as (_)

Answer 34

ferritin intestinal transferrin

Question 35

Erythroid progenitors obtain iron for hemoglobin synthesis from

Answer 35

1-plasma transferrin 2- from recycling of senescent erythrocytes by macrophages in bone marrow, spleen and liver.

Question 36

Excess Iron also stored in macrophages as

Answer 36

ferritin

Question 37

Globins are broken down to

Answer 37

amino acids

Question 38

porphyrin ring which is converted

Answer 38

to bilirubin

Question 39

In macrophages, (_) is a ferroxidase and facilitates the transfer of macrophage iron to transferrin

Answer 39

ceruloplasmin

Question 40

(_) downregulates ferroportin causing iron sequestration in macrophages.

Answer 40

hepcidin

Question 41

Whole body iron levels are regulated primarily at the level of absorption

Answer 41

by enterocytes

Question 42

active excretion of iron occurs by

Answer 42

bleeding or sloughing of iron- laden enterocytes

Question 43

Regulation of iron uptake by enterocytes and release of iron stores from macrophages and hepatocytes is mediated by the hormone

Answer 43

hepcidin

Question 44

where is hepcidin produced

Answer 44

liver

Question 45

decreases serum iron by decreasing iron absorption and preventing macrophages from releasing iron

Answer 45

hepcidin

Question 46

Hepcidin is regulated by

Answer 46

iron levels and erythropoiesis

Question 47

Hepcidin is also increased by inflammatory cytokines particularly

Answer 47

IL-6, and reduces available iron during inflammatory processes

Question 48

what increases iron absorption

Answer 48

Citrate and ascorbate

Question 49

what decreases iron absorption

Answer 49

Tannates

Question 50

Duodenal microvilli contain (_) to promote absorption of ferrous iron

Answer 50

ferric reductase

Question 51

what is a decrease in the total amount of red blood cells (RBCs) or hemoglobin in the blood, or a lowered ability of the blood to carry oxygen

Answer 51

Anemia

Question 52

Types of Anemia based on Clinical Picture

Answer 52

*Iron deficiency Anemia *Megaloblastic Anemia *Pernicious anemia *Aplastic Anemia *Hemolytic Anemia -Thalassemia anemia -Sickle cell Anemia

Question 53

Laboratory testing for For Iron Defeciency Anemia

Answer 53

* Serumiron * Totalironbindingcapacity(TIBC) * Serumferritin * Completebloodcount(CBC) * Bonemarrowbiopsy * Liverbiopsy

Question 54

Ferritin may be increased in serum by:

Answer 54

– Tissue release (hepatitis, leukaemia, lymphoma) – Acute phase response (tissue damage, infection, cancer)

Question 55

Causes of Iron Deficiency Anemia

Answer 55

*Increased iron utilization – Postnatal growth spurt – Adolescent growth spurt * Physiologic iron loss – Menstruation – Pregnancy * Pathologic iron loss – GI bleeding – Genitourinary (GU) bleeding * Decreased iron intake – Meat poor diet – Malabsorption

Question 56

General anemia’s symptoms

Answer 56

– Fatigue – Dizziness – Headache – Irritability – Palpitation – Dry, pale skin – Hair loss – Brittle nails